Multi-Phase Variable Reluctance Energy Harvester For Smart Bearing Hub Units

This paper reports on the design, optimization, and evaluation of a multi-phase variable reluctance energy harvester (MP-VREH) for integration into a smart bearing hub unit of large commercial vehicles. The MP-VREH converts rotational kinetic energy into electrical energy to enable the supply of smart electronic systems to monitor the bearing condition. The proposed design consists of a ferromagnetic toothed wheel and six identical m-shaped pickup units. Adhering to the space limitations of an example bearing hub unit, critical parameters, such as the pickup unit pole-piece structure, the magnet height, and the number of teeth, have been optimized using 3D finite element analysis. The optimized harvester provides output powers ranging from 0.46 W to 4.77 W at relevant rotational speeds of 100 to 400 RPM. This is deemed to provide sufficient energy for typical application scenarios.